Percent Increase and Decrease in Algebra

This video tutorial by Kirk Weiler from eMath Instruction covers the concepts of percent increase and decrease. It explains how to calculate the final value after a percentage change using both traditional and single calculation methods. The tutorial includes practical examples, such as population growth of beetles and temperature decrease of coffee, to illustrate these concepts. The video emphasizes the importance of understanding the remaining percentage after a decrease and provides exercises to practice these calculations.

What is the main focus of this lesson?

• Learning about algebraic expressions

• Understanding percent increase and decrease

• Finding the square root of numbers

• Solving quadratic equations

If a population of beetles increases by 6% from 350, what is the new population?

• 400

• 340

• 360

• 371

How can you increase a number by a certain percentage using a single calculation?

• Multiply by 1 plus the decimal version of the percentage

• Add the percentage to the number

• Divide by the percentage

• Multiply by the percentage

What is the result of increasing 440 by 12%?

• 492.8

• 450

• 500

• 480

Adriana's savings account increases by 2.5% per year. If she deposits $720, what will be her balance at the end of the year?

• $730

• $750

• $738

• $740

If the temperature of coffee decreases by 8% from 90°C, what is the new temperature?

• 70°C

• 85°C

• 80°C

• 82.8°C

How can you decrease a number by a certain percentage using a single calculation?

• Multiply by 1 minus the decimal version of the percentage

• Divide by the percentage

• Subtract the percentage from the number

• Multiply by the percentage

What is the result of decreasing 620 by 15%?

• 550

• 600

• 527

• 500

If the student enrollment decreases by 5% from 2300, what will be the new enrollment?

• 2000

• 2100

• 2200

• 2185

What is the price of gasoline after a 4.5% decrease from $3.80 per gallon?

• $3.70

• $3.80

• $3.50

• $3.63